Historical Tech Tree by Étienne Fortier-Dubois - An interactive technology tree spanning 3 million years of human history.

XofY OSM Geometry Viewer by Matt Whilden - A web tool for visualizing collections of OpenStreetMap features by type and by city.

Land Lines by Zach Lieberman, Matt Felsen, and the Data Arts Team - Draw a line and match it to a satellite image from around the world.

Library of Babel by Jonathan Basile - Comprehensive archive of every possible 3200 character text. Inspired by Jorge Luis Borges